Monochromatic Chess, a chess variant of unknown origin, maintains the standard rules and initial board position of regular chess. However, it introduces a unique twist: pieces that start on black squares are restricted to black squares throughout the game, while pieces that begin on white squares must exclusively occupy white squares throughout the gameplay. The implementation of this rule leads to intriguing implications for the gameplay:
- Pawn: In this variation, pawns are restricted to making only the initial two squares forward move, and they are limited to capturing as their sole method of advancing on the board.
- Knight: The standard knight’s typical move set becomes unusable in this variant. However, there are several potential solutions available to address this issue:
- A knight is allowed to make a double-jump.
- The piece is replaced by a 3-1 jumper, commonly referred to as a camel. The term “3-1” indicates that the camel can leap three squares horizontally or vertically, which is one square more than a regular knight, and one square vertically or horizontally. This replacement allows the camel to maintain its unique jumping ability while adapting to the monochromatic chess rules.
- Bishop: This is the only piece that doesn’t suffer from any restrictions. Bishops are bound to a single color in normal chess as well.
- Rook: A rook moves as usual, but can land only to a half of normally available squares.
- Queen: A queen is not limited diagonally, but faces the same restrictions as a rook, horizontally or vertically.
- King: A king can move only one step diagonally. Castling is allowed, but only on the king-side.
This variant is likely playable, but its wider adoption and popularity are primarily observed in composition chess rather than in regular gameplay. On the other hand, a real over-the-board game can lead to unusual situations. For instance, this is a modification of the Fool’s Mate:
Due to the monochromatic limitations, the g-pawn cannot block the check because moving to g3 would change the square color. Ergo, the black king is checkmated.